The invention relates to the field of beer dispensing and beer dispensing apparatus and, in particular, relates to a faucet for stabilizing foam draft beer as it is dispensed.
In the art of making beer, it is very important that the appearance of the beer in the glass be attractive to the user. While flavor is the aspect most talked about in beer, appearance is the first thing noticed by the customer and that makes it important. The shade and depth of color, the clarity, beading, type of head foam, the foam retention, and the foam cling, all contribute to making the initial impression. It is desirable that the foam atop a glass of beer dispensed from a faucet be smooth, creamy, be relatively stable and have an attractive taste. The incorporation of air into beer as it is dispensed at the faucet spout gives a head of very fine bubbles with excellent stability and a creamy slightly sweet desirable taste.
In application Ser. No. 735,443, there is disclosed a process and apparatus for incorporating air into beer after it leaves a conventional faucet spout by passing the beer through a perforated plate with small openings which break up the beer into smaller high velocity streams which pull air into the beer streams utilizing a Venturi effect. The pressure drop across the perforated plate starts the foaming process and the mixed beer, CO.sub.2 foam, and air is then passed through a screen to form small stable bubbles which result in the desired smooth, creamy and stable foam.
In Ser. No. 735,443 there is described the history of the efforts to dispense Irish stout and English beer with a desired head. These procedures were not totally successful, and some use nitrogen which result in additional expense. Several of the processes require the use of high pressure kegs, which, in turn, necessitates heavier duty installation in the pub.
Currently there are on the market so-called push back foam causing faucets, which work on the principle of restricting the beer at the valve seat, usually through on or two apertures on the shaft. These devices are believed to operate on the foaming caused by the pressure drop across the shaft wall and do not incorporate additional air or nitrogen into the foam.
These type devices, moreover, are not capable of producing a satisfactory type foam on the new light beers. The foam does not form a tight head and the foam "falls off", i.e., it goes flat quickly.
Accordingly, it is a principal object of this invention to provide a dispensing faucet which when in a first position will dispense flat beer and when in a second position will dispense a smooth, creamy and stable foam.
Furthermore, it is an object of this invention to provide a faucet which will dispense a stable, thick foam on a conventional "light-type" beer.
It is another important object of this invention to provide a beer dispensing faucet in which air is drawn into a stream of finely divided jets of beer, turbulence in the stream is created to mix the air into the beer, and a beer foam is dispensed which is comprised of bubbles of very small diameter, which foam is extremely stable over a period of time. This faucet is capable of creating this foam even with the light-type beers presently sold in this country. This faucet also is capable of dispensing flat beer so that the single faucet can dispense a glass of beer having a head of a smooth, creamy foam which is stable and long lasting.
These and other objects and advantages will become apparent in the drawings and description hereinafter set forth.